Many local telephone companies provide calling line identification services, such as those marketed as Caller ID and Caller ID-Deluxe. When a subscriber receives a telephone call, these services allow the subscriber to view on a display device the phone number from which the call originated and, in some cases, the name of the person making the call. These services are increasingly popular because, in many cases, they allow the called party to know both the identity of the calling party and the telephone number at which the calling party may be reached.
Current calling line identification services work best when the calling party is a residential subscriber calling from his or her residential telephone. In other cases, some of the displayed information may be missing or erroneous. For example, when a subscriber receives a call from a pay phone, the originating number will be displayed, but the calling party will not be identified. In the case of calls from some businesses, the displayed number will identify the directory number associated with an outgoing trunk line instead of the inbound telephone number the business uses to receive telephone calls. Callers who prefer to be called back on an 800 number face similar problems because 800 numbers are "fictitious" numbers that are translated to the directory numbers that are actually used to route the call. Although an 800 number is the proper call back number, it will not be displayed because the call did not originate from a subscriber line having that number.
In order to understand the drawbacks associated with current calling line identification services, it is helpful to understand how the services are provided. Basic Caller ID displays only the originating phone number. In order to accomplish this, the calling number is captured by the originating end office and sent to the terminating end office in an Initial Address Message, which is part of the call setup protocol. The terminating end office sends the calling number over the subscriber's line to the display device after the first ringing signal. The calling number is also referred to as the Incoming Calling Line Identification (ICLID) number.
Caller ID-Deluxe, which is also referred to as calling name delivery service, requires additional features available in an intelligent telecommunications network. Like the basic Caller ID scenario described above, the calling number is captured by the originating end office and sent to the terminating end office in an Initial Address Message. At that point, the terminating end office recognizes that the call is for a Caller ID-Deluxe subscriber and launches a calling name query on the intelligent network. The query message includes the calling number in the message's called party address field. A signaling transfer point (STP) performs a global title translation on the called party address to determine which service control point (SCP) to route the query to, and forwards the query to that SCP. The SCP searches the name database, which is built from the local phone company's billing records, for the calling number record and retrieves the associated name. The SCP returns the caller name to the terminating end office in a TCAP response. When the terminating office completes the call to the subscriber's phone, it sends the caller name and calling number, along with the current date and time, over the subscriber's line to the display device.
From the foregoing, it is apparent that in order for called party to know both the identity of the calling party and the telephone number at which the calling party may be reached, two things must happen. First, the calling number data received by the terminating end office must be the correct call back number. Second, the calling name database that is queried as a result of the terminating end office's calling name query must be able to match the caller's name with the calling number that was received at the terminating end office.
AT&T has addressed some of the drawbacks that relate to the provision of caller identification services in the context of credit card calls. U.S. Pat. No. 5,283,824 to Shaw describes a system in which the caller can specify the number that is sent to the terminating end office as the calling number. The system allows the caller to specify that the transmitted calling number data include the calling card number, which may include the customer's home or business number, the calling station number, or a personal identification number.
In the described system, the customer places a calling card call. The calling card system prompts the customer to enter the calling card number and to select the calling card number, calling telephone number, or personal identification number as the calling number data. The customer then dials the called party's phone number and the system sends the selected number to the terminating end office. At that point, the terminating end office launches a calling name query using the provided calling number.
If the user instructs the AT&T system to send a telephone number at which he or she may be called back (e.g., an office or hotel number, personal number, 800 number, wireless phone number, etc.), the Caller ID display device will not display the caller's name. If the user instructs the system to send his or her home telephone number, the display device will display the identity of the calling party (along with his or her home telephone number), but will not display the telephone number at which the calling party may actually be reached. Although the described system allows the user to send a meaningful number as the calling number, the calling party must determine whether the display device will display the proper call back number or properly identify the calling party.
In prior art caller identification systems, it is apparent that the only way to ensure that the displayed data properly identifies the calling party and provides a useful call back number is for the caller to place the call from a phone that is billed to him. This results in large part because the calling name databases are compiled from the local phone company's billing records.
Therefore, there is a need in the art for an improved system and method for providing calling party identification data, which will allow a calling party to ensure that the called party's display device displays both the calling party's proper identity and a valid call back number in situations where the calling party is not calling from a phone that is billed to him.